Unable to run script: Missing Run/Debug option in PyCharm

Problem

The option to run or debug a script is missing when right-clicking on a .py file in PyCharm.

Cause

The .py file extension was removed from the Python file types in File | Settings | Editor | File Types. As a result, PyCharm does not recognize the file as a Python script and does not provide the Run/Debug option.

Resolution

To resolve this issue:

1. Open PyCharm.
2. Navigate to File | Settings | Editor | File Types.
3. Add it manually by clicking on the + icon and entering *.py as below:
4. Apply the changes and restart PyCharm.